Support and General Use > Audio Playback, Database and Playlists

Linux, iHP-140 and mystery files

<< < (2/3) > >>

Chronon:
You need to supply a switch when you call the command in order to have it automatically repair problems.  You should be able to run fsck.vfat --help for further assistance.

bluebrother:

--- Quote from: spurty on May 07, 2009, 09:42:25 AM ---Not sure what reclaiming unused clusters is. This mean everything checks out?

--- End quote ---
FAT uses a simply linked lists for files. A big table (the FAT) contains a list of all clusters (the smallest fraction of the filesystem you can allocate). A file is split over several clusters which don't necessarily need to be successive. In the FAT, each cluster is marked as empty, points to the cluster following in the list of a file or is marked as last cluster in a list. This is the data by itself. Now there's the directory entries. Each entry points to the first cluster of that file. To access that file you now know where to start, then you can check the FAT about the next cluster that follows it and so on until you reached the last cluster used by the file.
If you delete a file you have to do two things: you need to remove the entry in the directory, i.e. the pointer to the first cluster. Second, you need to mark all the clusters of a file as empty, so when writing a new file those can get reused.

Due to this structure you can loose clusters by removing the directory entry but not marking the clusters (or only parts of the clusters) in the FAT as empty. If this happened the clusters won't get reused so you can't use the space allocated by those clusters. chkdsk / fsck now checks if all clusters marked as used have a pointer to them. If not, it's a lost cluster. If you create a new directory entry for them (i.e. file pointing to that data) you can delete it and thus regain the space it uses.

(I've left out some details in the explanation, but that's basically what lost clusters are.)

spurty:
@Chronon
I don't think Puppy has fsck.vfat installed by default. I think Die.net mentioned dosfsck when I searched fsck.vfat. Hope I didn't screw things up. It definitely did something. I thought the -vfat was the switch.
-v
Verbose mode.
-f
Salvage unused cluster chains to files.
-a
Automatically repair the file system.
-t
Mark unreadable clusters as bad.

The files I had on beforehand are still there and play fine as far as I know right now. But now there is a slew of weird FSCK files.

FSCK0000.REC
FSCK0001.REC
...
FSCK0111.REC

And these files actually have varying and substantial sizes. Can I (should I) delete these?

@bluebrother
Thanks for the explanation. Eventually I'd like to build a proper Linux box (Arch I think) and learn some of this stuff properly.

Chronon:
spurty, Ubuntu seems to consider dosfsck, fsck.vfat and fsck.msdos aliases of each other.  http://manpages.ubuntu.com/manpages/jaunty/man8/dosfsck.8.html

According to bluebrother's explanation, I would guess that those files are references to the aforementioned lost clusters, though I am not totally certain.

AlexP:
yes, they are recovered "files".  You can safely delete them, unless you want to check them for data you may have lost. 

Navigation

[0] Message Index

[#] Next page

[*] Previous page